It's going to be close to cost effective! or Off grid at 26 cents a KWh!

PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭
So I was doing some quick calculations on what i hope to achieve with my 'New' Off grid system vs the costs. I was surprised to find it's going to be close to cost effective!

Granted I'm figuring nothing for my labor, and I have gotten good deals, but rough costs for my 6.5 KW system;

Array 4KW - $3535 delievered + 2.5 KW $1000 delievered (warehouse accident salvage, new panels + broken that I had to discard properly actually I had a member here pick them up in hopes to use them.

Battery(24V 800Ah) - $2500 delievered

Charge controller - 2 classic lites - $950(Thanks NAWS!) + C60 on hand (@$200 value)

Combiner boxes @ $200 after rewire and fuses (1 rewired for 2 arrays)

E-Panel $200 delievered (New! Nice deal!)

Existing inverter 1800Watt Prosine $400 ( Unused off Ebay 5 years ago)

Balance of wiring, wire clips, Etc $400

Hand made aluminum mounts, PT wood framing, concrete footings $400(and a lot of work!)

So $9385 Current investment

Next 30 years -

Replace battery $3500 (expect lead and transport costs to go up)
Replace inverter 2x - $4000 (expect electronics to stay the same or go down)
Replace Charge Controllers 2X $3000

So roughly $20,000 over 30 years (not figuring in residual value of the 30 year old panels or the @$2500 Tax credit)

This will replace about 4KWh daily use for 245 days and 13KWh for 120 days each year(running A/C) or 2540 KWh for a cost of @ $666 a year /2540 or about 26 cent a KWh

I currently pay $25 a month + $.094 a KWh or $300 + $239 = $539

I'm sure I will find opportunity loads, and I could likely do this on the planned 4KW array, if the electronics hold up and the batteries it could be and Elec Coop prices go up then maybe I look like a genious, if the batteries die prematurely or I run into serious problems...

I was surprised it looked this good! Am I missing something? Is this just a product of an adulled mind, forced to stay up after pool league doing laundry?

I am lucky that our heat and my heaviest loads comes with extra sunshine, but I'm sure this would apply to others...
Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
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Comments

  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    Photowhit wrote: »
    So I was doing some quick calculations on what i hope to achieve with my 'New' Off grid system vs the costs. I was surprised to find it's going to be close to cost effective!

    Granted I'm figuring nothing for my labor, and I have gotten good deals, but rough costs for my 6.5 KW system;
    ...
    Battery(24V 800Ah) - $2500 delievered
    ...
    So $9385 Current investment

    Next 30 years -

    Replace battery $3500 (expect lead and transport costs to go up)
    Replace inverter 2x - $4000 (expect electronics to stay the same or go down)
    Replace Charge Controllers 2X $3000

    So roughly $20,000 over 30 years (not figuring in residual value of the 30 year old panels or the @$2500 Tax credit)
    ...

    I'm sure I will find opportunity loads, and I could likely do this on the planned 4KW array, if the electronics hold up and the batteries it could be and Elec Coop prices go up then maybe I look like a genious, if the batteries die prematurely or I run into serious problems...

    I was surprised it looked this good! Am I missing something? Is this just a product of an adulled mind, forced to stay up after pool league doing laundry?

    I am lucky that our heat and my heaviest loads comes with extra sunshine, but I'm sure this would apply to others...

    My first reaction is that regardless of how carefully you treat your batteries, and how good a set of batteries you get, a 15 year useful life seems out of line. The batteries usually end up being the largest recurring cost and therefore the largest component of the cost per Kwh.

    Can you be more specific about the batteries you are using?
    SMA SB 3000, old BP panels.
  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    inetdog wrote: »
    Can you be more specific about the batteries you are using?

    It's a GB Industries fork lift battery. NAWS sells Crown and states "...In a typical solar electric system they will normally last for about 20 years or more..."
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • stephendvstephendv Solar Expert Posts: 1,571 ✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    inetdog wrote: »
    My first reaction is that regardless of how carefully you treat your batteries, and how good a set of batteries you get, a 15 year useful life seems out of line.

    I was under the impression that forklift batts should have a 15+ life. In practice when used in warehouses with a DoD of 80% every day for 5 days a week, they typically last 5-8 years. They rated for a cycle life of 1500 cycles at 80% DoD, so 15+ or even 20+ in RE systems with MUCH shallower discharges should be expected no?
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!

    From the Giant Battery FAQ:
    Routinely charging the battery before it is 80% discharged is another common form of over charging. For example, if you only use
    the battery a few hours a day, it’s best to use it until it is truly in need of charging before actually plugging it in. Remember, each charge constitutes one cycle, so try not to charge unnecessarily.

    Its difficult for me to understand this advice. It seems contrary to most of the wisdom espoused on this forum. Maybe there is something to it...
    on another thread 'stephendv' reviews the Sunny Island and reports that it will not go into bulk charge mode until the battery SOC drops down to 70%.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • BB.BB. Super Moderators, Administrators Posts: 31,153 admin
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!

    Neat that your costs are working out so well for you... One missed issue--generally you will not use 100% every day, so if you use "only" 2/3rds of your available power on average (assuming you are not doing any sort of selling of power back to the power company), then:

    $0.26/0.67 = $0.39 per kWH

    Although, if I did the PV watts thing correctly, you are already assuming ~48% output of the system (including 0.52 system derating for off grid efficiency)...

    Don't see anything else (other than distilled water--if it is expensive for you to obtain) that would dramatically affect your return on investment.

    Regarding Battery Charging, Dave Sparks (as I recall) from his experience recommended recharging to >90% several times a week. Attempting 100% SOC every day is probably very hard on a battery bank in its own right.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    BB. wrote: »
    ...generally you will not use 100% every day, so if you use "only" 2/3rds of your available power on average ...

    Just off grid, the estimates are for my current usage, likely I won't have quite the 13 KW load for as long as this summer! but that's built into the calc.

    Costs I missed;

    Intrest on the 9K investment (though the economy is pretty flat right now).

    Frame cost only represents the 1st 4KW of array so an additional $4-600 for the next 2.6 KW which will shade the home.

    I had originally planned on a 2500 watt inverter, and might go ahead and get a 3500 Outback or a 4000 watt Magnum. so + $2000 (less the $400) I might go ahaed and use the Prosine for the first year, differing costs and keeping my attention on loads.

    This is not your typical system since the battery (800A x 24V = 19KWh) is well undersized for the Summer loads but our heat comes with sun and most of the load will be during the Day, hoping the oversized array will help keep me topped off most days.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    vtmaps wrote: »
    Its difficult for me to understand this advice. It seems contrary to most of the wisdom espoused on this forum. --vtMaps

    No, I think it has more to do with how Forklift batteries are charged and the strain it puts on them. Often they are charged at greater than C/8, their plates are a bit different and need to be equalized monthly. I take it this is advice for fork lift use and I plan on understanding and ignoring it. I think they just don't want the batteries hard charged for an hour between shifts.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • Eric LEric L Solar Expert Posts: 262 ✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    This is not your typical system since the battery (800A x 24V = 19KWh) is well undersized for the Summer loads but our heat comes with sun and most of the load will be during the Day, hoping the oversized array will help keep me topped off most days.

    Cool that the costs are working out for you. What you describe here is similar to how I've been using my battery-based but grid-supported system, which also has an undersized battery bank relative to the array, and it has worked out very well so far. We find that the solar-powered A/C runs most days until early evening, at which point we switch to the grid-connected central A/C to avoid stressing the batteries once the sun goes down, although the house is often cool enough from the daytime operation that the central A/C unit doesn't even turn on.

    Summer savings have been very good with this method; we have yet to see a utility bill over $40, which for a 2100 square foot house on the gulf coast is terrific (all electric). Although I doubt system will ever pay for itself, as I knew from the beginning, by keeping the battery bank small and finding ways to use power during the day it may not be that far from doing so either. How close it gets depends on equipment lifespan and replacement prices going forward, as mentioned above.

    This is kind of an aside, but if AGM batteries can be found relatively cheaply (in my area they aren't that much more than FLAs), you could push this sort of system design even further, assuming grid-support. Since the AGMs could take the higher charging and discharging rate of larger arrays and bigger loads, you could size the system with a very small battery bank/array ratio since you'd need only a fairly short run-time for an efficient HVAC system, such as a mini-split. Perhaps just two hours to 75 or 80% S.O.C. would let the mini-split run through typical partly cloudy daytime conditions. If the inverter could then switch to grid when the batteries were drawn to this level, you'd use the grid at night or for the roughly 10% (say) of days when there wasn't enough sun. I think such a system could potentially reach break-even if panel prices were low enough and someone DIY-ed it, even without a tax credit.
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    Photowhit wrote: »
    This is not your typical system since the battery (800A x 24V = 19KWh) is well undersized for the Summer loads but our heat comes with sun and most of the load will be during the Day, hoping the oversized array will help keep me topped off most days.

    Do the best you can to get efficient A/C units, as discussed in other threads here. The oversized array will be powering the A/C directly and reducing the amount of current drawn from the batteries as well as allowing a faster recharge during the time the A/C is cycled off. But your best bet would be an A/C design like some mini-splits that just throttle back their output to try to find a power level at which they run steadily instead of cycling. That will be easier on your batteries and your inverter.
    SMA SB 3000, old BP panels.
  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭
    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!
    inetdog wrote: »
    Do the best you can to get efficient A/C units, as discussed in other threads here. The oversized array will be powering the A/C directly and reducing the amount of current drawn from the batteries as well as allowing a faster recharge during the time the A/C is cycled off. But your best bet would be an A/C design like some mini-splits that just throttle back their output to try to find a power level at which they run steadily instead of cycling. That will be easier on your batteries and your inverter.

    Current plans are for a efficient Window unit in the bedroom running 24/7 on thermostat and a good size mini split (12K btu?) in the 'great room' (kitchen, family room) @30x15 run during the day. We'll where the financial pressures fall. I don't make much and have some other things coming up including replacing a car in the next couple years.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭

    It's been a while and I really need to do an update on this.

    In general it's all been running smooth, I've actually been heating 75-80% of my hot (and sometime luke warm) water needs with solar electric as an opportunity load.

    ...But the big news is, my local Power Coop is making me out to be a Genius! The local rates starting in about a month will include a accessibility fee of $39 a month. So without the tax credit or opportunity loads I'm pretty much at grid parity and with I'm running a bit cheaper than the grid!


    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • BB.BB. Super Moderators, Administrators Posts: 31,153 admin

    Ah... The old keep $/kWH rate cheap (or at least reasonable), and jack up the connection fees. Classic method to make money when customers have GT Solar.

    Here is my Northern California rate plan (I am code "X"):

    https://www.pge.com/tariffs/assets/pdf/tariffbook/ELEC_SCHEDS_E-6.pdf

    "Baseline" is about 300 kWH per month (over baseline, higher rates). I pay $10 per month connection fee (used to be $5).

    More or less, $0.19 to $0.29 per kWH for winter... $0.19 to $0.46 per kWH for summer rates (night lower, afternoon-evening higher rates).

    I keep telling myself, California is a beautiful place to live...

    -Bill

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • cow_ranchercow_rancher Solar Expert Posts: 117 ✭✭✭✭

    Re: I keep telling myself, California is a beautiful place to live...


    California is a beautiful place to have been from.

  • Dave AngeliniDave Angelini Solar Expert Posts: 5,550 ✭✭✭✭✭

    Beautiful places and decent weather are worth it in my opinion. That is why they fly into Puerto Vallarta in December.

    Happiness is the the key!

    We go where power lines don't !

    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭

    Re: It's going to be close to cost effective! or Off grid at 26 cents a KWh!

    BB. wrote: »

    The old keep $/kWH rate cheap (or at least reasonable), and jack up the connection fees.

    Did you notice in the 7 years since I first wrote this the charge for the first 1000 kWhs went from $.094 a KWh to $.122 a kWh! Almost a 30% increase, before the added user fees. and it all hits the poorest segment of the community. Pretty scary in 7 years.

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • jonrjonr Solar Expert Posts: 1,384 ✭✭✭✭

    >  $.094 a KWh to $.122 a kWh

    So < 4% a year. Higher than inflation, but I don't know about scary.

    I am available for custom hardware/firmware development

  • BB.BB. Super Moderators, Administrators Posts: 31,153 admin

    $0.46 per kWH for weekday summer afternoons? What is Hawaii's rates these days?

    This guy did some historical comparisions for PGE from 1999:

    https://www.quora.com/Pacific-Gas-Electric-Company-What-is-the-historical-increase-for-PG-E-rates-by-tariff-over-the-past-10-years

    I have been calculating PG&E’s E-20T rate for a specific customer load profile since 1999. Over that period, the annual average rate (including time of use demand and energy charges) has increased from $53.80/MWh in 1999 to $129.34/MWh in 2015, an average annual increase of about 5.6%. The variation each year has been as high as over 70% from 2000 to 2001 to as low as -12.6% from 2003 to 2004. However, since 2003, the average rate has gone from $106.38/MWh in 2003, which equates to an annual change of about 1.5%. The average annual change should be roughly the same for other commercial rate schedules, though the rates would likely be higher.

    And now we have something like 3x higher rates in the last few years.

    Their 2017 rates are pretty similar per kWH pricing as I am paying now:

    https://www.hawaiianelectric.com/billing-and-payment/rates-and-regulations/average-price-of-electricity

    https://www.electricitylocal.com/states/hawaii/ ($0.375 per kWH Hawaii average)

    I understand your concern about your increases... But compared to what I have have seen in recent California increases--Your entire $/kWH pricing is almost round off error vs our rates.

    But what is really going to kill many people (and what more utilities are trying) is the high per month fixed/minimum charges. Even if you have zero kWH bill, you still are paying $39 per month (which is ~320 kWH per month--Sort of close to what my monthly electric usage is (usually supplied by me GT solar system).

    -Bill

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭

    @jonr said ~ > $.094 a KWh to $.122 a kWh

    So < 4% a year. Higher than inflation, but I don't know about scary.

    That is in addition to the fixed charge going from $25 to $39 a 56% increase in fixed costs.

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • Dave AngeliniDave Angelini Solar Expert Posts: 5,550 ✭✭✭✭✭

    I saw an article in Motley Fool saying the price of solar panels from 1980 to now is down 99%. Going to be a tuff year to get panels when there is little profit in making them. Canadian Solar stock down from $25 to 18.

    Add in the federal credit being phased down starting next year and other constrained market issues I would not wait for the bottom if you need panels.

    Somebody has to pay for those Utility folks taking naps along the roads and in hotels. They sure are not cutting trees and brush around here.

    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭

    @Dave Angelini

    I don't lack for panels, I actually still have the 2700 watts mostly in the closet, 4 are up and mounted of the 13?) I never installed them got a deal on 4 - 250 watt panels for $200, again a fork lift accident. very slightly bent frames, no scaring. I put them at the extension of my rails. So I have 5000 watts up and running. The other 4 I mounted to use with a direct DC water heater, but chickened out.

    In addition, not like I needed them, I bought 6 - 310-330 watt panels left over from a larger community solar array installation. these were the 'extras' in case of problems. Paid a bit less than 25 cents a watt, thought I was going to do a largish pumping station, but for $450, what the heck. They are collecting sun, err dust in my vinyl shed. Bought them when cheap panels were hard to be had before the new tariffs were announce. One has a slightly bent frame and one has a tiny blemish on the back through the outer sealer. I coated it with liquid electrical tape/dip. So I have almost as much in reserve as I have up. I've tried to sell them cheap to a couple water pump installations, but people wanted new...


    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • MrM1MrM1 Registered Users Posts: 478 ✭✭✭
    edited March 2019 #22

    @Photowhit

    The other 4 I mounted to use with a direct DC water heater, but chickened out.

    Why did you chicken out?

    REC TwinPeak 2 285W 3S-3P 2.6kW-STC / 1.9kW-NMOT Array / MN Solar Classic 150 / 2017 Conext SW 4024 Inverter latest firmware / OB PSX-240 Autotransfomer for load balancing / Trojan L16H-AC 435Ah bank 4S connected to Inverter with 7' of 4/0 cable / 24 volt system / Grid-Assist or Backup Solar Generator System Powering 3200Whs Daily / System went Online Oct 2017 / System, Pics and Discussion
  • mcgivormcgivor Solar Expert Posts: 3,600 ✭✭✭✭✭✭

    Really, if I had surplus panels, they would be put to use, air conditioning in the hot months, water heating in the cold. Sitting idle they do nothing but gather dust, seems a shame.

    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • Dave AngeliniDave Angelini Solar Expert Posts: 5,550 ✭✭✭✭✭

    I am glad Photowit that you don't lack😎

    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • PhotowhitPhotowhit Solar Expert Posts: 5,409 ✭✭✭✭✭

    @mcgivor @MrM1

    I really should say I put it on the back burner again (Now 4 years, maybe 5)

    I had a bad winter last year, went to Christmas with Mom, her boyfriend, Brother and sister at rented cottage in Florida. Arrived for a week's stay Dec 22 to visit friends and help bring things to the cottage. Mom's back hurt, turns out she broke a vertebra in her back. I ended up getting back the first week of March. We had a very cold winter and my Pex lines cracked even though they had survived other winter temps in upper single digits/low teens. I had turned off the water and drained the water heater, but really dealing with that was enough to make me a bit nuts.

    Oddly, I have a 900 watt array set up. and 250 ft roll of 6 gauge. Even the PVC to run the wire under the tin can. Every thing but a relay. I planned to let the thermostat run a relay to control the DC power, eliminating most of the issues. We'll see, I've lost all motivation lately.

    Along with the time helping mom and her boyfriend settle into a routine, he is now 93 in hospice care, she at 84 still his primary care giver and he has dementia. As I was leaving he was going in to have heart shocked to come out of afib and he has a no revive order so a stressful time. He developed a story line where I brought people in the beat my mom. So seeing her has become difficult. I don't want to stress him. So sister brought her up to Callaway Garden in Sept for a family gathering, and No gathering this Christmas for the first time in many years. I'll go down and have a few meals with her in a couple weeks. All a bit stressful. Trying to do some other simple things to maintain sanity...

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • Dave AngeliniDave Angelini Solar Expert Posts: 5,550 ✭✭✭✭✭

    My Mom always said "Old age is not for Scissies" Sorry about yours! We have 3 over 95 and one who is 100. They all have dementia and various levels of being alive.

    Exercise and walk, eat good food with a balanced diet and leave out 4 helpings per week of red meat.

    I would say cut down on alcohol but as Frank Sinatra said. I feel sorry for people who do not take a drink. When they get up in the morning it is the best they will feel all day.

    Good Luck man!

    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • softdownsoftdown Solar Expert Posts: 3,494 ✭✭✭✭

    Did any Pex lines get exposed to sunlight? In my experience that is what destroys their ability to handle freezing.

    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • EstragonEstragon Registered Users Posts: 4,478 ✭✭✭✭✭

    It's usually my pex fittings (valves, elbows, etc) that crack with freezing, well before the pipe itself.

    Direct sunlight would certainly be a problem for the pipe itself though. I wonder how many problems lurk in walls from lazy contractors who left coils in the sun for a while before installation.

    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • softdownsoftdown Solar Expert Posts: 3,494 ✭✭✭✭

    Reminds me of my ongoing anger over so many code regulations. They require unneeded fittings and fittings cause most of the problems.

    The counties and cities own our homes. They just let us use them after paying extortionist property taxes.

    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • DaangeroussDanDaangeroussDan Registered Users Posts: 23 ✭✭

    It makes me sad to see people buying "old school" flooded lead acid now days. AGM's are so much better for high performing systems, charge and discharge at much higher rates, are no maintenance, do not off gas, spill proof, and therefore can be put in a climate controlled room where temperatures allow for maximum thermal performance. So much of the negative propaganda regarding solar off grid is due to the maintenance (or lack of it) required of "old school" flooded lead acid. Its antiquated , messy and innoficient, who wants to be married to their battery bank and risk missing a maintenance cycle to devastating and cascading effects. Here is my view on batteries; https://www.youtube.com/watch?v=ycjrC-3A79E

  • mike95490mike95490 Solar Expert Posts: 9,089 ✭✭✭✭✭


    Dan. Slow it down. Not every system is suited for AGM. They may work well for you, but they are NOT forgiving of much overcharge before they vent and loose electrolyte. Beginners dialing in their system, would much rather loose a $500 bank of "big box store" GC2 flooded, than a $1500 bank of AGM. And when AGM get old and tired, their failure mode often includes overpressure and venting and if a neophyte has stacked them in a closet, it's going to be a sad day

    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

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